Villa Sistemi Medicali ENDOS AC, Руководство пользователя

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USER'S MANUAL
Technical data
(Rev. 7) ENDOS AC/ACP - CE 23
5.2 5.2 5.2 5.2 Method for measuring technical factors Method for measuring technical factors Method for measuring technical factors Method for measuring technical factors
kV
p
KVp value is defined as the stationary value of high voltage applied to
the tube which settles on load after preheating time.
KV
p
value is measured by a non-invasive instrument, with accuracy of
over 2%, to the nominal value of line voltage.
A direct high voltage measurement can be made only by disassembling
the tubehead.
This operation can be executed only in the factory .
mA The anodic current value is defined as the average value of stationary
current which settles on load after pre-switching time.
The anodic current value is measured using a digital voltmeter
measuring the voltage drop at the ends of the resistance from 1 k
Ω
, 1%
assembled on the tubehead. To take this measurement, remove the side
plastic plug of the tube support; connect the ground voltmeter terminal
on the yellow/green cable clamp screw and insert the positive terminal
into the contact at the end of the grey cable. The digital voltmeter must
be selected on DC, and the relation of transformation is given by 1 mA =
1V. Execute an exposure of at least 1 sec.
t The exposure time value is the time during which the value of the anodic
peak current exceeds 25% of the steady state value. The time taken to
reach this condition is called "pre-heating time".
The measurement must be taken at nominal line voltage, measuring the
anodic current wave-form on the 1k
Ω
resistance and using a memory
oscilloscope.
Exposure time measurements using non-invasive equipment can
lead to systematic errors in exposure time measurements which
cannot be quantified and which depend on the equipment used for
measuring (see paragraph 5.3).